2-chloro-3-aryl-4-methyl-imidazolium chlorides



United States Patent 3,136,774 2-CHLORO-3-ARYL-4-METHYL-IMIDAZOLIUM CHLORIDES Paul J. Stolfel, St. Louis, Mo., assignor to Monsanto Company, St. Louis, Mo., a corporation of Delaware No Drawing. Filed Dec. 22, 1961, Ser. No. 161,380

12 Claims. (Cl. 260-309) This invention relates to the synthesis of new and 'use- 7 ful 4-methyl-imidazol-2-ones and to new and useful 2- chloro-4-methyl-irnidazolium chloride precursors therefor.

The 4-methyl-imidazol-2-ones of this invention can be represented by the formula wherein R is a hydrocarbyl radical containing up to 12 carbon atoms and is free of acetylenic unsaturation or said hydrocarbyl radical having substituents such as lower alkoxy, nitro, and halogen having an atomic weight in the range of 35 to 80 (i.e., chlorine or bromine) and wherein R is phenyl (i.e., C H or said phenyl radical having substituents such as lower alkyl, lower alkoxy, nitro, and halogenof atomic weight in the range of 35 to 80 (i.e., chlorine or bromine).

The 2-chloro-4-methyl-imidazolium chloride precursors of the aforementioned 4-methyl-imidazol-2-ones possess resonance about the 2 carbon atom and can be represented by the formula wherein R and R have the aforedescribed significance and wherein but one of the -ws is a double bond the other being a single bond.

The 4-methyl-imidazol-2-ones of this invention are prepared by initially reacting phosphorus pentachloride with N-propargyl substituted urea of the formula CHEC CH 0 wherein R and R have the aforedescribed significance and then treating the 2-chloro-4-methyl-imidazolium chloride so obtained with base, e.g.,.alkali metal hydroxides such as sodium or potassium hydroxide. These procedural operations can be set forth schematically as follows lPCls wherein R and R have the aforedescribed significance and wherein the respective s have the aforedescribed significance.

3,136,774 Patented June 9, 1964 Example I To a suitable reaction vessel equipped with a thermometer, agitator and reflux condenser is charged 50.0 parts by weight of phosphorus pentachloride, 120 parts by weight of benzene, and 67.0 parts by weight of 1-(3,4-dichlorophenyl)-3-isopropyl-3-(prop-Z-ynyl) urea. The so charged mass is refluxed for 4 hours. The reaction mass is cooled to room temperature and filtered. The filter cake is washed with diethyl ether and dried. The dried solid product (60.5 parts by weight) is 2-ch1oro-3-(3,4- dicblorophenyl)-l-isopropyl-4-methyl-imidazolium chloride. After recrystallizing from chloroform this solid melted at 275 C. with decomposition.

To a suitable reaction vessel equipped with a thermometer and agitator is charged 17.0 parts by weight of 2- chloro 3 (3,4 dichlorophenyl)-1-isopropyl-4-methylirnidazolium chloride and 50 parts by weight of water. The resulting solution is made alkaline with 25 parts by weight of 20% aqueous sodium hydroxide. The precipitate is filtered off and dried. The dried solid product (13.1 parts by weight) is 3-(3,4-dichlorophenyl)-l-isopropyl 4-methyl imidazol-Z-one. After recrystallizing from ethyl acetate the melting point is found to be 112.1l12.6 C.

r 7 Example Il Example III Employing the procedure of Example I but replacing 1 (3,4-dichlorophenyl)-3-isopropyl-3-(prop-2-yny1) urea with anequimolecular amount of 1-(4-bromophenyl)-3 methyl-3-(prop-2-ynyl) urea there is obtained 2-chloro- 3 (4-bromophenyl)-l,4-dimethyl-imidazolium chloride, which chloride on treatment with aqueous potassium hydroxide provides 3-(4-bromophenyl)-1,4-dimethyl-imidazol-2-one.

Example IV v To a suitable reaction vessel equipped with a thermometer, agitator and reflux condenser is charged 36.9 parts by weight of phosphorus 'pentachloride, parts by weight of benzene, and 44.5 parts by weight of 1-(4- chlorophenyl)-3-isopropy1-3-(prop-2-ynyl) urea. The so charged mass is refluxed for 6 hours. The reaction mass is cooled to room temperature and filtered. The filter cake is washed with diethyl ether and dried. The dried solid product (40.2 parts by weight) is 2-chloro-3-(4- chlorophenyl) 1-isopropyl-4-methyl-imidazolium chloride. After recrystallizing from chloroform this solid melted at 268 C. with decomposition.

To a suitable reaction vessel equipped with a thermometer and agitator is charged 15.3 ports by weight of 2 chloro 3-(4-ch1orophenyl)-1-isopropyl-4-methyl-imidazolium chloride and 100 parts by weight of water. The resulting solution is made alkaline with 20 parts by Weight of 20% aqueous sodium hydroxide. The precipitate is filtered off and dried. The dried product (10.7 parts by weight) is 3-(4-chlorophenyl)-l-isopropyl-4-methylimidazol-Z-one. After recrystallizing from ethyl acetate the melting point is found to be 137.6-138.5 C.

Example V Employing the procedure of Example IV but replacing 1-(4-chlorophenyl)-3-isopropyl-3-(prop-2-ynyl) urea with an equimolar amount of 1-(4-chlorophenyl)-3-phenyl-3-(prop-2-ynyl) urea there is obtained 2-chloro-3-(4- chlorophenyl)-1-phenyl-4-methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(4-chlorophenyl)-l-phenyl-4-methylimidazol-Z-one.

Example VI Employing the precedure of Example IV but replacing 1 (4 chlorophenyl)-3-isopropyl-3-(prop-Z-ynyl) urea with an equimolar amount of 1-(4-chlorophenyl)- 3-benzyl-3-(prop-2-ynyl) urea there is obtained '2-chloro- 3 -(4-chlorophenyl)-1-benzy1-4-methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(4-chlorophenyl)-1-benzyl-4-methyl-imidazol-Z-one.

Example VII Employing the procedure of Example IV but replacing l-(4-chlorophenyl)-3-isopropy1-3-(prop-Z-ynyl) urea with an equimolar amount of 1-(4-chlorophenyl)-3-(2-ethylhexyl)-3-(prop-2-ynyl) urea there is obtained Z-chloro- 3 (4-chlorophenyl) -1- (2-ethylhexyl) -4-methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(4-chlorophenyl)-1-(2-ethylhexyl-4-methyl-imidazol Z-one.

Example VIII Employing the procedure of Example IV but replacing 1- (4-chlorophenyl -3-isopropyl-3-(prop-Z-ynyl) urea with an equimolar amount of 1-(4-chlorophenyl)-3-(4-nitrophenyl)-3-(prop-2-ynyl) urea there is obtained 2-ch1oro- 3- 4-chlorophenyl)-1-(4-nitrophenyl-4-methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(4-chlorophenyl)-1-(4-nitrophenyl)-4-methyl-imidazol-2-one.

Example IX To a suitable reaction vessel equipped with a thermometer, agitator and refiux condenser is charged 40.0 parts by weight of phosphorus pentachloride, 100 parts by weight of benzene, and 49.0 parts by weight of 1-(2-chlorophenyl)-3-isopropyl-3-(prop-2 ynyl) urea. The so charged mass is refluxed for 6 hours. The reaction mass is cooled to room temperature and filtered. The filter cake is washed with diethyl ether and dried. The dried solid product (11.9 parts by weight) is 2-chloro-3-(2- chlorophenyD-l-isopropyl 4 methyl-imidazolium chloride. After recrystallizing from chloroform this solid melted at 254 C. with decomposition.

To a suitable reaction vessel equipped with a thermometer and agitator is charged 15.2 parts by weight of 2- chloro 3 (Z-chlorophenyl)-1-isopropyl-4-methyl-imidazolium chloride and 50 parts by weight of water. The resulting solution is made alkaline with 20 parts by weight of 20% aqueous sodium hydroxide. The precipitate is filtered off and dried. The dried product (11.5 parts by weight) is 3-(2-chlorophenyl)-1-isopropyl-4- methyl-imidazol-Z-one. After recrystallizing from ethyl acetate the melting point is found to be 115.5-116.4 C.

Example X Employing the procedure of Example IX but replac ing l-(2-chlorophenyl)-3-isopropyl-3-(prop-Z-ynyl) urea with an equimolecular amount of 1(2-chloro-4-methylphenyl)-3-n-butyl-3-(prop-2-ynyl) urea there is obtained 2-chloro 3-(2-chloro-4-methylphenyl-1-n-butyl-4-methylimidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(2-chloro-4-methylphenyl) -1-n-butyl-4-methyl-imidazol-Z-one.

Example XI Employing the procedure of Example IX but replac- 4 ing 1-(Z-chlorophenyl)-3-isopropyl-3-(prop-Z-ynyl) urea with an equimolar amount of 1-(2-chloro-4-methylphenyl)-3-sec. butyl-3-(prop-2-ynyl) urea there is obtained 2-chloro 3 (2-ch1oro-4-methylphenyl)-l-sec. butyl-4- methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(2- chloro-4-methylphcny1)-1-sec. butyl 4-methyl-imidazol- 2-one.

Example XII Employing the procedure of Example IX but replacing 1-(2-chlorophenyl)-3-isopropyl-3-(prop-Z-ynyl) urea with an equimolar amount of 1-(2-chloro-4-nitrophenyl)- 3-sec. buty1-3-(prop-2-yny1) urea there is obtained 2- chloro-3-(2-chloro-4-nitrophenyl)-1-sec. buty1-4-methylimidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(2-chloro-4-nitrophenyl)-l-sec. butyl-4-methyl-imidazol-2-one.

Example XIII To a suitable reaction vessel equipped with a thermometer, agitator and refiux condenser is charged 25.0 parts by weight of phosphorus pentachloride, 100 parts by weight of benzene, and 30.0 parts by weight of 1-(4- nitrophenyl)-3-isopropyl-3-(prop-2-ynyl) urea. The so charged mass is refluxed for 6 hours. The reaction mass is cooled to room temperature and filtered. The filter cake is washed with diethyl ether and dried. The dried solid product (24.4 parts by weight) is 2-chloro-3-(4- nitrophenyl)-1-isopropyl-4-methyl-imidazolium chloride which material is highly hygroscopic.

To a suitable reaction vessel equipped with a thermometer and agitator is charged 15.8 parts by weight of 2- chl0ro-3- (4:-nitrophenyl )-1-isopropyl-4-methy1- imidazolium chloride and 50 parts by weight of water. The resulting solution is made alkaline with 30 parts by weight of 20% aqueous sodium hydroxide. The precipitate is filtered oil and dried. The dried product (11.1 parts by weight) is 3-(4-nitrophenyl)--1-isopropyl-4-methyl-imidazol-Z-one. After recrystallizing from ethyl acetate the melting point is found to be 114.7115.7 C.

Example XIV Employing the procedure of Example XIII but replacing 1-(4-nitrophenyl)-3-isopropy1-3-(prop-Z-ynyl) urea with an equimolar amount of 1-(2,4-dinitrophenyl)13- ethyl-3-(prop-2-ynyl) urea there is obtained 2-ch1oro-3- (2,4-dinitrophenyl) -1-ethyl-4-methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(2,4-dinitrophenyl)-1-ethyl-4-methyl-imidazol-Z-one.

Example XV Example XVI Employing the procedure of Example XIII but replacing 1-(4-nitrophenyl)-3-isopropyl-3-(prop-Z-ynyl) urea with an equimolecular amount of 1-(2,4-dinitrophenyl)- 3-(pent-Z-enyl)-3-(prop-2-ynyl) urea is there obtained 2- chloro 3-(2,4-dinitrophenyl)-l-(pent-Z-enyl)-4-methylimidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(2,4-dinitrophenyl)- 1-(pent-Z-enyl)-4-mcthyl-imidazol-2-one.

Example XVII Employing the procedure of Example XIII but replacing l (4-nitrophenyl)-3-isopropyl-3-(prop-2-ynyl) urea with an equimolecular amount of 1-(2,4-dinitro- 3 phenyl)-3-(4-biphenylyl)-3-(prop-2-ynyl) urea there is obtained 2-chloro-3- (2,4-dinitrophenyl 1- (4-biphenylyl) 4-methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(2,4-dinitrophenyl) -l (4-biphenylyl -4-methyl-imidazol-2-one.

Example XVIII Employing the procedure of Example XIII but replacing 1-(4-nitropheny1)-3-isopropyl-3-(prop-Z-ynyl) urea with an equimolecular amount of 1-(2,4-dinitrophenyl)- 3-(Z-naphthyl)-3-(prop-2-ynyl) urea there is obtained 2- chloro 3 (2,4-dinitrophenyl)-l-(2-naphthyl)-4-methylimidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(2,4-dinitrophenyl) l- (2-naphthyl -4-methyl-imidazol-2-one.

Example XIX To a suitable reaction vessel equipped with a thermometer, agitator and reflux condenser is charged 44.0 parts by weight of phosphorus pentachloride, 100 parts by weight of benzene, and 46.0 parts by weight of 1-(4-methylphenyl)-3-isopropyl-3-(prop-Z-ynyl) urea. The so charged mass is refluxed for 6 hours. The reaction mass is cooled to room temperature and filtered. The filter cake is washed with diethyl ether and dried. The dried solid product (41.4 parts by weight) is 2-chloro-3-(4- methylphenyl)-l-isopropyl-4-methylimidazolium chloride which material is highly hygroscopic.

To a suitable reaction vessel equipped with a thermometer and agitator is charged 28.5 parts by weight of 2- chloro 3-(4-methylphenyl)-1-isopropyl-4-methyl-imidazolium chloride and 100- parts by weight of water. The resulting solution is made alkaline with 50 parts by weight of 20% aqueous sodium hydroxide. The precipitate is filtered off and dried. The dried product (15.8 parts by weight) is 3-(4-methylphenyl) -1-isopropyl-4-methyl-imidazol-2-one. After recrystallizing from ethyl acetate the melting point is found to be 1l8.7-l19.4 C.

Example XX Employing the procedure of Example XIX but replacing 1-(4-methylphenyl)-3-isopropyl-3-(prop-Z-ynyl) urea with an equimolecular amount of l-(3,5-dimethylphenyl)- 3-isobutyl-3-(prop-2-ynyl) urea there is obtainedZ-chlor 3-(3,5-dimethylphenyl)-1-isobutyl-4-methyl-imidazoliurn chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(3,5.-dimethylphenyl)-1-isobutyl-4-methyl-imidazol-2-one.

Example XXI Employing the procedure of Example XIX but replacing 1-(4-methylphenyl)-3-isopropyl-3-(prop-Z-ynyl) urea with an equimolecular amount of 1-(4-t. butylphenyl)- 3-isobutyl-3-(prop-Z-ynyl) urea there is obtained 2-chloro- 3 (4 t. butylphenyl)-l-isobutyl-4-methy1-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(4-t. butylphenyl)-1-isobutyl- 4-methyl-imidazol-2-one.

Example XXII Employing the procedure of Example XIX but replacing 1-(4-methylphenyl)-3-isopropyl-3-(prop-Z-ynyl) urea with an equimolecular amount of 1-(4-isohexylphenyl)-3- isobutyl-3-(prop-2-ynyl) ureat here is obtained 2-chloro- 3 (4 isohexylphenyl)-l-isobutyl-4-rnethyl-imidazolium chloride, which chloride'on treatment with aqueous sodium hydroxide provides 3-(4-isohexylphenyl)-ldsobutyl-4 methyl-imidazol-Z-one.

Example XXIII Employing the procedure of Example XIX but replacing 1-(4-methylphenyl)-3-isopropyl-3-(prop-Z-ynyl) urea with an equimolecular amount of 1-(4-cumyl)-3-isobutyl 3-(prop-2-ynyl) urea there is obtained 2-chloro-3-(4 cumyl)-1-isobutyl-4-methyl-imidazolium chloride, which chloride on treatment with aqeuous sodium hydroxide provides 3- (4-cumyl) -1-isobutyl-4-methyl-imidazol-2-one.

Example XXIV Employing the procedure of Example XIX but replacing l-(4-methylphenyl)-3-isopropyl-3-(prop-Z-ynyl) urea witha n equimolecular amount of l-(3,5-dimethylphenyl)- 3-cyclohexyl-3-(prop-2-ynyl) urea there is obtained 2 chloro 3 (3,5-dimethylphenyl)-l-cyclohexy1-4-methylimidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(3,5-dimethylphenyl) 1 -cyclohexy1-4-methyl-imidazol-Z-one.

Example XXV To a suitable reaction vessel equipped with a thermometer, agitator and reflux condenser is charged 34.0 parts by weight of phosphorus pentachloride, parts by weight of benzene, and 43.0 parts by weight of l-(3,4- dich1orophenyl)-3-allyl-3-(prop-2-ynyl) urea. The so charged mass is refluxed for 6 hours. The reaction mass is cooled to room temperature and filtered. The filter cake is washed with diethyl ether and dried. The dried solid product (49.0 parts by Weight) is 2-chloro-3-(3,4- dichlorophenyl) l-allyl-4-methyl-imidazolium chloride. After recrystallizing from chloroform this solid melted at 200 C. with decomposition.

To a suitable reaction vessel equipped with a thermometer and agitator is charged 16.9 parts by weight of 2- chloro-3-(3,4-dichloropheuyl)-l-allyl-4-methyl imidazolium chloride and 50 parts by weight of water. The resulting solution is made alkaline with 20 parts by Weight of 20% aqueous sodium hydroxide. The precipitate is filtered off and dried. The dried product (7.1 parts by weight) is 3-(3,4-dichloropheny1)-l-allyl-4-methyl-imidazol-Z-one. After recrystallizing from ethyl acetate the melting point is found to be 62.162.7 C.

Example XXVII Employing the procedure of Example XXVI but replacing l-(3,4-dichlorophenyl)-3-allyl-3-(prop 2 enyl) urea with an equimolecular amount of l-(2,4,5-trichlorophenyl)-3-allyl-3-(prop-2-ynyl) urea there is obtained 2- chloro-3-(2,4,5-trichlorophenyl)-1-allyl-4 methyl imidazolium chloride, which chloride on treatment with aque ous sodium hydroxide provides 3-(2,4,5-trichlorophenyl)- 1-allyl-4-methyl-imidazol-2-one.

Example XX VIII Employing the procedure of Example XXVI but replacing l-(3,4-dichlorophenyl)-3-allyl-3-( prop 2 ynyl) urea with an equimolecular amount of 1-(2-chloro-4- nitrophenyl)-3-allyl-3-(prop-2-ynyl) urea there is obtained 2-chloro-3-(2-chloro-4-nitrophenyl)-1-allyl 4 methylimidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(2-chloro-4-nitrophenyl) l-allyl-4-methyl-imid azol-Z-one.

Example XXX Employing the procedure of Example XXVI but replacing l-(3,4-dicluorophenyl)-3-allyl-3-(prop 2 ynyl) urea with an equimolecular amount of 1-(3-chloro-4- bromophenyl)-3-allyl-3-(prop-2-ynyl) urea there is obtained 2-chloro-3-(3-chloro-4-bromophenyl) 1 allyl 4- methyl-imidazolinum chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(3- chloro-4-bromophenyl) -1-allyl-4-methyl-imidazol-2-one.

Example XXXI Employing the procedure of Example XXVI but replacing 1-(3,4-dichlorophenyl)-3-allyl-3-(prop 2 ynyl) urea with an equimolecular amount of 1-(2,4,5-trichlorophenyl)-3-(dodec-1-enyl)-3-(prop-2-ynyl) urea there is obtained 2-chloro-3-(2,4,5-trichlorophenyl)-1-(dodec 1- enyl)-4-methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(2,4, S-trichlorophenyl)-1-(dodec-l-enyl)-4-methyl-irnidazol-2- one.

Example XXXll To a suitable reaction vessel equipped with a thermometer, agitator and reflux condenser is charged 23.0 parts by weight of phosphorus pentachloride, 100 parts by weight of benzene, and 28.5 parts by weight of 1-(3,4- dichlorophenyl)-3-n-propyl-3-(prop-Z-ynyl) urea. The so charged mass is refluxed for 6 hours. The reaction mass is cooled to room temperature and filtered. The filter cake is Washed with diethyl ether and dried. The dried solid product (22.2 parts by Weight) is 2-chlo1'o-3- (3,4-dichlorophenyl)-l-n-propyl-4-methy1 imidazolium chloride. After recrystallizing from chloroform this solid melted at 238 C. with decomposition.

To a suitable reaction vessel equipped with a thermometer and agitator is charged 17.0 parts by weight of 2- chloro-3-(3,4-dichlorophenyl) -1-n-propyl-4-methyl imidazolium chloride and 50 parts by weight of Water. The resulting solution is made alkaline with 20 parts by Weight of 20% aqueous sodium hydroxide. The precipitate is filtered off and dried. The dried product (7.9 parts by weight) is 3- 3,4-dichlorophenyl -1-n-propyl-4-methylimidazol-2-one. After recrystallizing from ethyl acetate the melting point is found to be 62.963.4 C.

Example XXXIII Employing the procedure of Example XXXII but replacing 1-(3,4-dichlorophcnyl)-3-n-propyl-3 (prop 2- ynyl) urea with an equimolecular amount of 1-(3,4-dichlorophenyl)-3-n-dodecyl-3-(prop-Z-ynyl) urea there is obtained 2-chloro-3-(3,4-dichlorophenyl)-l-n-dodecyl-4- methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(3,4-dichlorophenyl)-1-n-dodecyl-4-methyl-imidazol-2-one.

Example XXXIV Employing the procedure of Example XXXII but replacing 1-(3,4-dicl1lorophenyl)-3-n-propyl-3 (prop 2- ynyl) urea with an equimolecular amount of 1-(3,4-dichlorophenyl)-3-n-amyl-3-(prop-2-ynyl) urea there is obtained 2-chloro-3-(3,4-dichlorophenyl)-l-n-amyl-4 meth yl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(3,4-dichlorophenyl)-1-n-amyl-4-methyl-imidazol-2-one.

Example XXXV Employing the procedure of Example XXXII but replacing 1-(3,4-dichlorophenyl)-3-n-propyl-3 (prop 2- ynyl.) urea with an equirnolecular amount of 1-(3,4-dichlorophenyl)-3-n-octyl-3-(prop-2-yny1) urea there is obtained 2-chloro-3- 3 ,4-dichlorophenyl 1 -n-octyl-4 -methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hyroxide provides 3-(3,4-dichlorophenyl)- 1-n-octy1-4-rnethyl-imidazol-Z-one.

Example XXXVI Employing the procedure of Example XXXII but replacing 1-(3,4-dichlorophenyl)-3-n-propyl-3 (prop 2- ynyl) urea with an equimolecular amount of 1-(3,4-dichlorophenyl)-3-(2-ethoxyethyl)-3-(prop 2 ynyl) urea there is obtained 2-chloro-3-(3,4-dichlorophcnyl)-l-(2- ethoxyethyl)-4-methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3- 3 ,4-dichlorophenyl -1- Z-ethoxyethyl -4-methylimidazol-Z-one.

Example XXXVII Employing the procedure of Example XXXII but replacing 1-(3,4-dichloropheny1)-3-n-propyl-3 (prop 2- ynyl) urea with an equimolecular amount of l-(3,4-dichlorophenyl)-3-(2-chloroethyl)-3-(prop 2 ynyl) urea there is obtained 2-cnloro-3-(3,4-dichlorophenyl)-1-(2- chloroethyl)-4-methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(3,4-dichlorophenyl)-1-(2-chloroethyl)-4-methylimidazol-2-one.

Example XXXVIII Employing the procedure of Example XXXII but replacing l-(3,4-dichlorophenyl)-3-n-propyl-3 (prop 2- ynyl) urea with an equirnolecular amount of l-(3,4-dichlorophenyl)-3-(4-nitro-n-butyl)-3-(prop-2 ynyl) urea there is obtained 2chloro-3-(3,4-dichlorophenyl)-l-(4- nitro-n-butyl)-4-methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(3,4-dichlorophenyl)-1-(4-nitro-n-butyl)-4 methyl-imidazol-Z-one.

Example XXXIX To a suitable reaction vessel equipped with a thermometer, agitator and reflux condenser is charged 15.0 parts by weight of phosphorus pentachloride, parts by Weight of benzene, and 12.0 parts by weight of l-phenyl- 3-isopropyl-3-(prop-2-ynyl) urea. The so charged mass is refluxed for 6 hours. The reaction mass is cooled to room temperature and filtered. The filter cake is Washed with diethyl ether and dried. The dried solid product (12.9 parts by weight) is 2-chloro-3-phenyl-l-isopropyl- 4-methyl-imidazolium chloride. After recrystallizing from chloroform this solid melted at 204 C. with decomposition.

To a suitable reaction vessel equipped with a thermometer and agitator is charged 8.0 parts by weight of 2-chloro-3-phenyl-1-isopropyl-4-methyl-imidazolium chloride and 50 parts by weight of Water. The resulting solution is made alkaline with 20 parts by weight of 20% aqueous sodium hydroxide. The precipitate is filtered off and dried. The dried product (5.9 parts by weight) is 3-pl1enyl-1-isopropyl-4-methyl-imidazol-2-one. After recrystallizing from ethyl acetate the melting point is found to be 53.354.1 C.

Example XL Employing the procedure of Example XXXIX but replacing l-phenyl-3-isopropyl-3-(prop-Z-ynyl) urea with an equimolecular amount of 1-phenyl-1-ethyl-3-(prop-2- ynyl) urea there is obtained 2-chloro-3-phenyl-1-ethyl-4- methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-phenyl- 1-ethyl-4-metl1yl-imidazol-2-one.

Example X LI Employing the procedure of Example XXXIX but replacing 1-phenyl-3-isopropyl-3-(prop-Z-ynyl) urea with an equimolecular amount of l-phenyl-l-(2-choloroallyl) 3-(prop-2-ynyl) urea there is obtained 2-chloro-3-phenyl- 1-(2-chl0roallyl)-4-methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-phenyl-1-(2-chloroallyl)-4-methyl-imidazol-2- one.

Example XLIII Employing the procedure of Example XXXIX but replacing l-phenyl-3-isopropyl-3-(prop-Z-ynyl) urea with an equimolecular amount of l-phenyl-l-(Z-isopropoxyethyl)-3-(prop-2-ynyl) urea there is obtained 2-chloro- 3 phenyl 1 2 isopropoxyethyl) 4 methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides.3-phenyl-l-(2-isopropoxyethyl) -4-methyl-imidazol-2-one.

Example XLI V Employing the procedure of Example XXXlX but replacing 1-phenyl-3-isopropyl-3-(prop-Z-ynyl) urea with an equimolecular amount of l-phenyl-l-[2-(2-chloroethoxy)ethyl]-3-(prop-2-ynyl) urea there is obtained 2- chloro 3 phenyl l [2 (2 chloroethoxy)ethyl]- 4-methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-phenyl- 1-[2-(2-chloroethoxy)ethyl]-4-methyl-imidazol-2-one.

Example XLV Employing the procedure of Example XXXIX but replacing 1-phenyl-3-isopropyl-3-(prop-Z-ynyl) urea with an equimolecular amount of l-phenyl-1-(2,3-dibromopropyl)-3-(prop-2-ynyl) urea there is obtained 2-chloro- 3 phenyl 1 (2,3 dibromopropyl) 4 methyl-imidazolinum chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-phenyl-l-(2,3-dibromopropyl) -4-methyl-imid azol-2-one.

Example XLVI Employing the procedure of Example XXXIX but replacing 1-phenyl-3-isopropyl-3-(prop-2-ynyl) urea with an equimolecular amount of l-phenyl-1-(4-ethoxyphenyl)-3-(prop-2-ynyl) urea there is obtained 2-chloro-3- phenyl-l-(4-ethoxyphenyl)-4-methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-phenyl-1-(4-ethoxyphenyl)-4-methyl-imidazol-Z-one.

Example XLVII To a suitable reaction vessel equipped With a thermometer, agitator and reflux condenser is charged 11.0 parts by weight of phosphorus pentachloride, 100 parts by weight of benzene, and 16.6 parts by weight of 1,3-di- (3,4-dichlorophenyl)-3-(prop-2-ynyl) urea. The so charged mass is refluxed for 6 hours. The reaction mass is cooled to room temperature and filtered. The filter cake is washed With diethyl ether and dried. The dried solid product (7.5 parts by weight) is 2-chloro-1,3-di(3,4- dichlorophenyl)-4-methyl-imidazolium chloride. After recrystallizing from chloroform this solid melted at 235 C. with decomposition.

To a suitable reaction vessel equipped With a thermometer and agitator is charged 4.4 parts by weight of 2-chloro- 1,3-di(3,4-dichlorophenyl)-4-methyl-imidazolium chloride and 20 parts by weight of water. The resulting solution is made alkaline with 10 parts by Weight of aqueous sodium hydroxide. The precipitate is filtered oil and dried. The dried product (1.8 parts by weight) is 1,3-di(3,4-dichlorophenyl)-4-methyl-imidazol-2-one. After recrystallizing from ethyl acetate the melting point is found to be 164.7-165.2 C.

. 10 Example XLVII] Employing the procedure of Example XLVII but replacing 1,3-di(3,4-dichlorophenyl)-3-(prop-2-ynyl) urea with an equimolecular amount of l,3-di(4-nitrophenyl)- 3-(prop-2-ynyl) urea there is obtained 2-chlor0-l,3-di(4- nitrophenyl)-4-methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 1,3-di(4-nitrophe11yl)-4-methyl-imidazol-2-one.

Example XLIX Employing the procedure of Example XLVII but replacing 1,3-di(3,4-dichlorophenyl)-3-(prop-2-ynyl) urea with an equimolecular amount of l,3-di(4-ethoxyphenyl)-3-(prop-2-ynyl) urea there is obtained 2-chloro-1,3- di(4-ethoxyphenyl)-4-methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides l,3-di(4-ethoxyphenyl)-4-methyl-imidazol-Z-one.

Example L Employing the procedure of Example XLVII but replacing 1,3-di(3,4-dichlorophenyl)-3-(prop-2-ynyl) urea with an epimolecular amount of l,3-di(2-chloro-4-nitrophenyl)-3-(prop-2-ynyl) urea there is obtained 2-chloro- 1,3-di(2-chloro 4 nitrophenyl) 4 methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 1,3-di(2-chloro-4-nitrophenyl)- 4-methyl-imidazol-2-one.

Example LI Employing the procedure of Example XLVII but replacing l,3-di(3,4-dichlorophenyl)-3-(prop-2-ynyl) urea with an equimolecular amount of l,3-di(3-chloro-4-bromophenyl)-3-(prop-2-ynyl) urea there is obtained 2-chloro 1,3 di(3 chloro 4 bromophenyl) 4 methylimidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides l,3-di(3-chloro-4- bromophenyl) -4-methyl-imidazol-2-one.

Example LII Employing the procedure of Example XLVII but replacing 1,3-di(3,4-dichlorophenyl)-3-(prop-2-ynyl) urea with an equimolecular amount of l,3-di(3,4-dimethoxyphenyl)-3-(prop-2-ynyl) urea there is obtained 2-chloro- 1,3-di(3,4-dimethoxyphenyl)-4-methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 1,3-di(3,4-dimethoxyphenyl)-4-methyl-imidazol-Z-one.

Example LIII Employing the procedure of Example XLVII but replacing 1,3-di(3,4-dichlorophenyl)-3-(prop-2-ynyl) urea with an equimolecular amount of 1,3-di(4-isohexylphenyl)-3-(prop-2-ynyl) urea there is obtained 2-chloro-l,3- di(4-isohexylphenyl) 4 methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides l,3-di(4-isohexylphenyl)-4-methyl-imidazol-2-one.

4 Example LIV To a suitable reaction vessel equipped with a thermometer, agitator and reflux condenser is charged 24.7 parts by weight of phosphorus pentachloride, parts by Weight of benzene, and 31.0 parts by weight of 1-(4-ethoxyphenyl)-3-isopropyl-l-(prop-Z-ynyl) urea. The so charged mass is refluxed for 6 hours. The reaction mass is cooled to room temperature and filtered. The filter cake is washed with diethyl ether and dried. The dried solid product (23.0 parts by weight) is 2-chloro-3-(4- ethoxyphenyl)-l-isopropyl 4 methyl-imidazolium chloride.

To a suitable reaction vessel equipped with a thermometer and agitator is charged 12.0 parts by weight of 2 chloro 3 (4 ethoxyphenyl) 1 isopropyl 4- methyl-imidazolium chloride and 50 parts by weight of Water. The resulting solution is made alkaline with 20 parts by Weight of 20% aqueous sodium hydroxide. The

l. l. precipitate is filtered off and dried. The dried product (9.5 parts by weight) is 3-(4-ethoxyphenyl)-l-isopropyl- 4-methyl-imidazol-2-one. After recrystallizing from ethyl acetate the melting point is found to be 75 .576.2 C.

Example LV Employing the procedure of Example LIV but replacin g 1- (4-ethoxyphenyl -3-isopropyl-3- (prop-2-ynyl) urea with an equimolecular amount of l-(3,4-dimethoxyphenyl)-3-n-propyl-3-(prop)-2-ynyl)urea there is obtained 2- chloro 3 (3,4 dimethoxyphenyl) l n propyl 4- rnethyl-imidazolium chloride which chloride on treatment with aqueous sodium hydroxide provides 3-(3,4-dimethoxyphenyl) -1-n-propyl-4-rnethyl-imidazol-2-one.

Example LVI Employing the procedure of Example LIV but replacing l- (4-ethoxyphenyl) -3-isopropyl-3- (prop-2-ynyl) urea with an equimolecular amount of l-(3,4-dimethoxyphenyl)-3- (but-Z-enyl)-3-(prop-2-ynyl) urea there is obtained 2- chloro 3 (3,4 dimethoxyphenyl) l (but 2 enyl)- 4-methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(3,4-dimethoxyphenyl) 1 (but 2 enyl) 4 methyl imidazol-2-one.

Example LVII Employing the procedure of Example LIV but replacing 1- (4-ethoxyphenyl) -3-isopropyl-3- (prop-Z-ynyl) urea with an equimolecular amount of 1-(3,4-dimethoxyphenyl)-3-fl-phenethyl-3-(prop-Z-ynyl) urea there is obtained 2 chloro 3 (3,4 dimethoxyphenyl) l fi phenethyl-4-methyl-imidazoliu1n chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(3, 4 dimethoxyphenyl) 1 p phenethyl 4 methyl imidazol-Z-one.

Example LVIII Employing the procedure of Example LIV but replacing 1-(4-ethoxyphenyl) -3-isopropyl-3-(prop-2-ynyl) urea with an equimolecular amount of l-(3,4-dimethoxyphenyl)-3-cinnamyl-3-(prop-Z-ynyl) urea there is obtained 2- chloro 3 (3,4 dimethoxyphenyl) 1 cinnamyl 4- methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(3,4-dimethoxyphenyl l -cinnamyl-4-methyl-imidazol-2-one.

Example LIX Employing the procedure of Example LIV but replacing l-(4-ethoxyphenyl)-3-isopropyl-3-(prop-Z-ynyl) urea with an equimolecular amount of l-(3,4-dimethoxyphenyl)-3-(2,3-dichloropropyl)-3-(prop-3-ynyl) urea there is obtained 2-chloro-3-(3,4-dimethoxyphenyl)-l-(2,3-dichloropropyl)-4-methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3 (3,4 dimethoxyphenyl) l (2,3 dichloropropyl)- 4-methyl-imidazol-2-one.

Example LX Employing the procedure of Example LIV but replacin g 1- (4-ethoxyphenyl -3 -isopropyl-3- (prop-2-ynyl) urea with an equimolecular. amount of 1-(3,4-dimethoxy phenyl)-3-(4-chlorophenyl)-3-(prop-2-ynyl) urea there is obtained 2-ch1oro-3-(3,4-dimethoxyphenyl -l-(4-chlorophenyl)-4-methyl-imidazolium chloride, which chloride on treatment with aqueous sodium hydroxide provides 3-(3,4-dimethoxyphenyl) l (4-chlorophenyl)-4-methylimidazol-Z-one.

In the preparation of the 2-chloro-4-methyl-imidazolium chlorides a wide range of reaction conditions can be employed provided the reaction system is fluid (i.e., a temperature above the freezing point of the system up to and including the systems boiling point), however, in general reaction temperatures in the range of from about 50 C. to about 120 C. ordinarily are satisfactory. In general in reaction the N-(prop-2-ynyl) urea with phosphorus pentachloride it is preferable to employ an inert organic solvent such as benzene, toluene, xylene, heptane, etc. Ordinarily the urea reactant and phosphorus pentachloride will be used in substantially equimolecular amounts, however, a substantial excess of either reactant can be employed. While pressures above or below atmospheric can be employed in general the pressure employed will be atmospheric.

In the preparation of the 4-methyl-i1nidazol-2-ones from the corresponding 2-chloro-4-methyl-imidazolium chloride by treatment with alkali metal hydroxide an aqueous system will be employed. In general the treating temperature will be in the range of from about 10 C. to about 100 C. Ordinarily the molar ratio of alkali metal hydroxide to the imidazolium chloride reactant will be 2:1, however, a slight excess of alkali metal hydroxide can be employed.

The 4-methyl-imidazol-2-ones of this invention are bacteriostatically active against Micrococcus pyogenes var. aareas. The 2-chloro-4-methyl-imidazolium chlorides of this invention display insect repellent activity against the southern armyworm. Of the 4-methyl-irnidaZol-2-0nes and the 2-chloro-4-methyl-imidazolium chlorides those of the aforedescribed formulae wherein R is lower alkyl (i.e., methyl, ethyl, propyl, butyl, amyl, or the various isomeric forms thereof containing up to 5 carbon atoms) are preferred. Another preferred class are those of the foregoing formulae wherein R is a chlorophenyl radical of the empirical formula C H Cl wherein n is a whole number from 1 to 3.

While this invention has been described with respect to certain illustrative embodiments it is to be understood that it is not so limited and that variations and modifications thereof obvious to those skilled in the art can be made without departing from the spirit or scope of this invention.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows.

I claim:

1. A 2-chloro-4-methyl-imidazolium chloride of the wherein the respective s are unlike and selected from the group consisting of a double bond and a single bond, wherein R is selected from the group consisting of hydrocarbyl radicals having up to 12 carbon atoms and selected from the group consisting of cyclohexyl, phenyl, naphthyl, biphenylyl, alkyl substituted phenyl, phenyl substituted alkyl, alkyl and alkenyl and said hydrocarbyl radicals having substituents selected from the group consisting of lower alkoxy, nitro, and halogen having an atomic Weight in the range of to 80, and wherein R is selected from the group consisting of phenyl and said phenyl radical having substituents selected from the group consisting of lower alkyl, lower alkoxy, nitro, and halogen having an atomic weight in the range of 35 to 80.

2. 2-chloro-3-(chloro substituted phenyl)-l-(alkyl)-4- (methyl)-irnidazolium chloride wherein the alkyl substituent has up to 12 carbon atoms, and wherein the chloro substituted phenyl substituent has from 1 to 3 chlorine atoms.

3. 2-chloro-3-(chloro substituted phenyl) 1 (lower alkyl)-4-methyl-imidazolium chloride wherein the chloro substituted phenyl has from 1 to 3 chlorine atoms.

4. 2-chloro 3 (monochlorophenyl) 1 isopropyl-4- methyl-imidazolium chloride.

5. 2-chloro-3-(dichlorophenyl) l isopropyl-4-methyl-imidazolium chloride.

6. 2-chloro 3 (3,4-dichlorophenyl) 1 isopropyl-4- methyl-imidazolium chloride.

7. 2-chloro-3-(2-chlorophenyl) 1 isopropyl-4-metl1- yl-imidazolium chloride.

8. 2-chloro-3-(4-chlorophenyl) 1 isopropyl-4-methyl-imidazolium chloride.

9. 2-chloro-3-phenyl-1-isopropyl 4 methyl-imidazolium chloride.

10. 2-chloro-3-(4-nitrophenyl) 1 isopropyl-4-methyl-imidazolium chloride.

11. The method of making the compounds of claim 1 which comprises reacting at a temperature above the freezing point of the system up to and including the systems boiling point phosphorus pentachloride with an N-(prop-Z-ynyl) substituted urea of the formula wherein R and R have the same significance as in claim 1.

12. The method of making the compounds of claim 2 which comprises reacting at a temperature in the range of from about 50 C. to about 120 C. and in the presence of an inert organic solvent phosphorus pentachloride with an N-(prop-Z-ynyl) substituted urea of the formula References Cited in the file of this patent UNITED STATES PATENTS 2,493,319 Shonle et a1. Ian. 3, 1950 2,707,186 Duschinsky Apr. 26, 1955 OTHER REFERENCES Beilsteins Handbuch der Organischen Chemie, 4th edition, volume 23, page 48, Berlin, Springer, 1936.

Schipper et al.: In: Heterocyclic Compounds, volume 5, pages 247-48, ed. by Elderfield, New York, Wiley, 1957. 

1. A 2-CHLORO-4-METHYL-IMIDAZOLIUM CHLORIDE OF THE FORMULA 